Abstract:Objective To explore the clinical effect of self-ligating bracket+Twin-block functional appliance in the treatment of patients with class Ⅱ division Ⅰ malocclusion. Methods A total of 80 patients with class Ⅱ division Ⅰ malocclusion admitted to the Dental Clinic of Ophthalmology and Otorhinolaryngology Department, the No.2 Hospital of Zhangjiakou from May 2019 to May 2021 were selected as the research objects. They were divided into treatment group A (n=39) and treatment group B (n=41) by random number table method. The treatment group A was treated with straight wire appliance, and the treatment group B was treated with self-ligating bracket + modified Twin-Block appliance. The changes of profile morphology, Pancherz analysis results, appearance satisfaction and quality of life were compared between the two groups. Results The proportion of effective changes in profile tissue in treatment group B was 97.56%, which was higher than 79.49% in treatment group A (P<0.05). B-OLP, Pg/ OLP and is/OLP in treatment group B were higher than those in treatment group A (P<0.05). The satisfaction of treatment group B was 97.56%, which was higher than 79.49% of treatment group A (P<0.05). The scores of each dimension of quality of life in treatment group B were higher than those in treatment group A (P<0.05). Conclusion The effect of self-locking bracket+Twin block functional appliance in the treatment of class Ⅱ division Ⅰ malocclusion is effective, which can reconstruct the profile tissue, optimize the facial aesthetics, and improve the quality of life of patients. Meanwhile, the patient's satisfaction is high, which is worthy of clinical application.